The present invention has, as a goal, the scrubbing or cleaning of vapors from a DT. Particulate matter such as dust is precipitated out of the vapors so that the dust is not ingested into an evaporator used in a processing system. Various attempts have been made to provide solutions to problems dealing with cleaning such vapors. One such attempt has been to employ a cyclone on top of the DT. Such a solution has, however, proven expensive, and it affords undesirable pressure drop. Such a solution is unsatisfactory because it diminishes the efficiency of the overall system.
Another proposed solution has been to provide means for introducing a spray of solvent in the DT. Such a spray is typically located at a point where the vapors go into a duct which allows them to exit the DT. This solution has also proven to be unsatisfactory, however, since the solvent moistens the meal below. In consequence, energy waste occurs. Even further, however, such a solution has proven inefficient in accomplishing cleaning of the vapors.
Another proposed solution is to provide a water wash. As in the case of solvent cleaning, the water wash is positioned in the duct exiting the DT. Again, however, this solution has inherent problems. As in the case of solvent cleaning, unnecessary energy is expended.
It is to these deficiencies that the present invention is directed. The present invention incorporates a concept which allows cleaning of vapors from a DT of particulate matter before the vapors are conveyed to an evaporator.